Carrier route record
UAORD→SLC
United Airlines · Chicago to Salt Lake City
- Flights
- 1,069
- Period
- July 2025 to June 2026
- Share of route
- 33%
- Carriers
- 5
Historical statistics for July 2025 to June 2026, not live status. For today’s flights, check with United Airlines.
United on ORD to SLC sits in the middle of the pack with a C+. About seven flights in ten arrive on time by the DOT's definition, 6 points worse than the national rate of 77.6%. The late ones land about an hour behind schedule. That rests on 1,069 flights. The strongest carrier on the route with a full sample, Delta Air Lines, flew 1,011 at 71.8% on time.
The national on-time rate over the same period is 77.6%, so United on ORD to SLC runs 6 points behind the country as a whole. Across a thousand flights that is about 59 extra late arrivals.
Key figures
On time
71.7%
Arrivals under 15 minutes late, of 1,058 completed flights
Avg delay
64 min
Across delayed arrivals only, not all flights
Cancelled
0.84%
National rate is 1.81%
Whole route
68.8%
Every carrier on ORD to SLC, 3,198 flights
These figures cover 1,069 flights between July 2025 and June 2026. Beyond the headline rate, 9.5% of arrivals land a full hour or more behind schedule. That is the number that wrecks a connection, and it is not visible in an on-time percentage alone.
Carrier by carrier
United against every carrier on ORD to SLC
United flew 1,069 of the 3,198 flights on ORD to SLC, about 33% of it. Its 71.7% on time is 3 points better than the route as a whole, which runs 68.8%. Ranked by on-time rate it is number two of five carriers on the route, where the range runs from Delta at 71.8% to SkyWest at 56.2%. Two of those carriers flew fewer than 365 flights here, so treat their positions as rough.
The choice of carrier is not cosmetic here. Delta Air Lines arrives on time 71.8% of the time; American Airlines manages 64.2%. Sample sizes sit next to every figure, because a two-point gap across 969 flights means less than a ten-point one.
| Airline | Flights | On time | Avg delay | Cancelled | Grade |
|---|---|---|---|---|---|
| Delta Air Lines | 1,011 | 71.8% | 105 min | 0.79% | C+ |
| United Airlines (this page) | 1,069 | 71.7% | 64 min | 0.84% | C+ |
| American Airlines | 969 | 64.2% | 69 min | 1.96% | D |
| Envoy Airthin sample | 36 | 61.1% | 48 min | 0.00% | D+ |
| SkyWest Airlinesthin sample | 113 | 56.2% | 87 min | 0.88% | D+ |
Delta leads American by 8 points. Real, but small enough that a better departure time on the weaker carrier can outweigh it.
Departure window
When United runs best on this route
Departure time matters more here than the choice of carrier. The gap between the best and worst window is 30 points, against 8 points between the best and worst carrier. Each bar is the on-time rate for flights scheduled inside that window.
- 5am–8am15 flights—
- 8am–11am417 flights78.0%
- 11am–2pm283 flights80.4%
- 2pm–5pm16 flights—
- 5pm–8pm62 flights50.0%
- 8pm–5am276 flights58.2%
Scale runs 40% to 85%. Rows with fewer than 30 flights show a dash.
The 5pm–8pm window is where this operation falls apart: 50.0% on time, against 80.4% for the 11am–2pm slot. By evening the aircraft flying these rotations have absorbed a full day of small delays and there is no slack left to recover in. The 8am–11am window is the busiest, with 417 flights scheduled in it.
Across the year
United on ORD to SLC through the year
December is the weak month at 56.2% on time, against 84.4% in February. Winter delays cluster: a single storm system can account for most of a month's shortfall, so an average December hides both very good weeks and genuinely unflyable days. March was the busiest month here, with 121 flights.
Across the week, Tuesday is the strongest day at 79.7% on time and Sunday the weakest at 63.2%. 17 points is a smaller lever than departure hour, but it is free.
Delay causes
Why United runs late on this route
One category carries most of the weight here. Late-arriving aircraft accounts for 49% of the 19,000 delay minutes carriers reported, and the remaining four split what is left. The split is by minutes rather than by flights, so a few very long delays count for as much as many short ones.
- 49%Late-arriving aircraft
- 28%Carrier
- 14%National Airspace System
- 8%Extreme weather
49% of delay minutes trace back to a late-arriving aircraft, meaning the plane was already behind before it got here. That is a cascade, and cascades start small and grow through the day. Across 19,000 reported delay minutes here, that single category outweighs weather by 6 to one. It is the strongest argument for booking the first departure of the morning, when the aircraft has been sitting at the gate overnight with nothing to inherit. The split is drawn from 19,205 reported delay minutes.
Cancellations are rare at 0.84%, below the national 1.81% and low enough to earn the plus on the grade. Roughly one flight in 100 is called off; the risk here is arriving late, not not arriving.
Connections and stage length
What a delay here costs
For anyone connecting, the number to weigh is not the on-time rate but the tail behind it. 9.5% of arrivals land a full hour or more behind schedule, against 8.1% nationally. A 45-minute layover does not survive that, and no amount of walking quickly changes it. Ninety minutes is the honest minimum here, and two hours if the onward flight is on a separate ticket.
The 1,250 miles between these two airports put this in the middle of the US network, around two and a half to three hours of block time. That is enough cruise to absorb a ten-minute late pushback and not enough to absorb thirty. It is also long enough that the aircraft usually flies three or four legs a day rather than six, which slows how fast delay compounds.
The return leg is a different operation and performs like one: it runs 75.4% on time across 1,069 flights, 4 points above this direction. Departure banks, aircraft rotations and the congestion at each end all differ, so scoring the two directions together would average away a real 4 points of difference.
One caution: this is a thin sample. 1,069 flights over twelve months is enough to clear this site's floor but not enough to pin the rate down tightly, and a single bad week moves it by more than a point. Treat the grade as a rough reading.
What to do with this
Booking United on ORD to SLC
Put together: treat all of this as provisional. 1,069 flights over twelve months is enough to clear this site's floor and not enough to be confident to better than a couple of points. The 71.7% headline is the most reliable number on the page; the hour and month splits below it are built on a few dozen flights each. 1,058 completed flights over 12 months sit behind that.
Related
Where to go next
- ORD to SLC, every carrier
- United on SLC to ORD, the return leg
- Delta Air Lines on ORD to SLC71.8%
- American Airlines on ORD to SLC64.2%
- SkyWest Airlines on ORD to SLC56.2%
- United Airlines network-wide record
- Chicago O'Hare International (ORD) delay statistics
- Salt Lake City International (SLC) delay statistics
- Why the first flight of the morning is statistically safest
- The best time of day to fly, according to 7.04 million flight records
Source: US DOT Bureau of Transportation Statistics, on-time performance data, July 2025 to June 2026. Last updated 15 September 2026; recomputed monthly. How this data is collected.